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What are the survival rates for colorectal cancer by stage?

Survival rates are often used by doctors as a standard way of discussing a person's prognosis (outlook). Some patients may want to know the survival statistics for people in similar situations, while others may not find the numbers helpful, or may even not want to know them. If you decide that you don’t want to know them, stop reading here and skip to the next section.

The 5-year observed survival rate refers to the percentage of patients who live at least 5 years after their cancer is diagnosed. Of course, many people live much longer than 5 years (and many are cured).

Relative survival rates, like those in the table, compare the observed survival with what would be expected for people without the cancer. This helps to correct for the deaths caused by something besides cancer and is a better way to see the effect that the cancer has on survival.

In order to get 5-year survival rates, doctors have to look at people who were treated years ago. Improvements in treatment since then may result in a more favorable outlook for people now being diagnosed with colorectal cancer.

Survival rates are often based on previous outcomes of large numbers of people who had the disease, but they cannot predict what will happen in any particular person's case. Knowing the type and the stage of a person's cancer is important in estimating their outlook. But many other factors can also affect a person's outlook, such as the grade of the cancer, the genetic changes in the cancer cells, the treatment received, and how well the cancer responds to treatment. Even when taking these other factors into account, survival rates are at best rough estimates. Your doctor can tell you if the numbers below may apply, as he or she is familiar with the aspects of your particular situation.

Survival rates for colon cancer, by stage

The numbers below come from the National Cancer Institute's SEER database, looking at people diagnosed with colon cancer between 2004 and 2010.

Stage

5-year Relative
Survival Rate

I

92%

IIA

87%

IIB

63%*

IIIA

89%*

IIIB

69%

IIIC

53%

IV

11%

*These numbers are correct : patients with stage IIIA or IIIB cancers have better survival than those with stage IIB cancers.

These statistics are based on a previous version of the staging system. In that version, there was no stage IIC (those cancers were grouped considered stage IIB). Also, some cancers that are now considered stage IIIC were classified as stage IIIB, while some other cancers that are now considered stage IIIB were classified as stage IIIC.

Survival rates for rectal cancer, by stage

The numbers below come from the National Cancer Institute's SEER database, looking at people diagnosed with rectal cancer between 2004 and 2010.

Stage

5-year Relative
Survival Rate

I

87%

IIA

80*%

IIB

49*%

IIIA

84%

IIIB

71%

IIIC

58%

IV

12%

*These numbers are correct; survival was better for some stage III cancers than for some stage II cancers.

These statistics are based on a previous version of the staging system. In that version, there was no stage IIC (those cancers were considered stage IIB). Also, some cancers that are now considered stage IIIC were classified as stage IIIB, while some other cancers that are now considered stage IIIB were classified as stage IIIC.